SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6d979379e3030f0f9664cfcc4b8e64276ec77848d7cce5c7f64e18aae99b85b' 
  AND token = 'R0KNDpV7vF/X5hPjCgys4UC/ELKWuqPMOAVbBdTSDiI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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