SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd645100ff4da1447c63b763dfdca9a40b24faf8ff55ccdba261911469c22d73b' 
  AND token = 'kBKyGEhd0+3zBn5nn9KxjSvX83+kwXVWd2+GLH+1oqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}