SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c49c0967a6a7caa32f5eac64d16d5b4ed434e05fbfa912ea24e12a6f872492b9' 
  AND token = 'L1qxpRCHhD8lWDuU6DBDIJq3a0wcyLbvcvikuyY+U58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}