SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '395a4997a93f21c9efe743a60646c78f05f6ddeb3cde4758b277cb9f14a1da3e' 
  AND token = 'NIFbs4oPaeAW32I2waXoloD73aCw3xM+9Fv/0kSIXRQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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