SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17578524c2527bebfa4beca5933ece4ad0431fa7471e864a895c99231069542a' 
  AND token = 'wn0mviA65JzlF7Ueq7wu52RpmqyWP2KQW1yY1L9I/LY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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