SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8abfcea15c86082e1802721ddf82431d90c70e070958c239b52c4a94cd65f9e3' 
  AND token = 'XjSe5WyFwzlY5oiWJlbGhKTpn2LrvM5ZNoNikDXKea4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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