SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'bad7387f07486c70080463a761e32db73a28b514573df059fb73aa2786fcd09f' 
  AND token = '1uqvbhgIBH2pw+HyMteZkDuh3s8Ri4LTe5MJDzI3g54=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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