SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a490e4ac6d3441d7b42a209c45ca90a9bbff0ab59cc88d9d5454f14355dde20' 
  AND token = 'CTKmU4oYLm0pzhMB6qrod9Q4bMHRArLtfDpBFkRqGFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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