SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '57c870cbdb7b8a3dd1034267b970218d87cea4e0809477edda71cfc2567024aa' 
  AND token = 'TI2Ke7IqBFfW9HMYLsLyaMAnc92FhrwH+fZakmuuxwA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00074

JSON explain

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