SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13cc26edef55a3756f906187744bccb25bb8f978650412829f285423edd211b9' 
  AND token = 'i/tZUVjbBB282Gy+KKp+1BuV/v/c5Isq6F2dkq7MK14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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