SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '630614fe2252e44cd7706dac4ab88b8215f44c2a91a9b155453e81122ff0eceb' 
  AND token = 'luV85Bn/Xw8sYvM/xSrW/RYo6SK0Gg2Mrk2VZUpgenM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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