SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f31a60a5b48afaf3bf67cffed520a7cabaecbc061c5b9b1322400d0f4a86e764' 
  AND token = 'dyQxAUjD0VLCcw0PDBRMpVgUcfYqUoyIkkPcCDDwoO8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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