SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2bc7e32cd5647ab3084c1976ca92411e870e7167ed73da1da30ff2223dccb5d' 
  AND token = 'nL09ZIKOLRqp/ZU1A8DM1gsu8EXZlPsX3p09Qv2RnN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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