SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bd86564f0d61fc187beb6e3e787084cbf3cbc2abcf5c47991993161a08c88574' 
  AND token = 'iUcRt9eadGOOQaXfrCn8tk7HJvYgxyo9CiujOeQliU8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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