SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a5eceaba64fd8585331670849b64039b541dae30c852858575a837103bc1bd7c' 
  AND token = 'qiQ+yusHaCeWd8Y6l1CiMRiyzq9uBTaiAOJ3AVU2sI4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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