SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb4d6ad5c010f21952883fad04c62bb87836d1f222dccbdd2ebd06de39764a1' 
  AND token = 'zOZ6SW85RjK1+BJTQ0HWpHPtWNHR6+d2M0z/4LysTIs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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