SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae37992c75ba757d454d9c37c35f9b136e29d2d5569ecb1d8dca2480198b6db1' 
  AND token = 'jdQ6IMUUHFOGzVB/ffRDVqFqMUNb6bphWKrTMJQvv4E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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