SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '25bc51687ef849122139154550194611bfc2cf37d3735332cea541600450d933' 
  AND token = 'd0rbwrHmKXUj56i9RRFRESntiAaoszP9zHf73hefABk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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