SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8693ac8dec2149e5288da7bafb274f86e1f12304a678067df2993e54e4ce2bd6' 
  AND token = '6iIDUCJoYZkG0lCEz/7H5n+i0oTj9f3RUuY8QkrJirI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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