SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb158da299d03398c43e9527335877d2b2feac7709d7692376cee552e2391e1f' 
  AND token = 'PwvZ2IOo/ONtzTEgahubuhmntq+ZaTh6UWDeDVPV61o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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