SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd773a70ad94722be04f0f2ef600fae35e29c8bbc7aec3ac714517d225fd1ede6' 
  AND token = 'M69jZKqi7sD+LTBuGjLOxECQ+B4f3s1prTqsMHQFLI0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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