SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce1896ff8a448198ef000e2056618635ae7363ce000388188a3c542afd719099' 
  AND token = 'gNOzWsA5r03QvVwidwaId9gSL0clxk0JLmThNnSH/Vk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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