SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '701517be644b6cec448f2c37f9dd811d58c9ea46230a7fb4644d363ec2cd1f0c' 
  AND token = 'TU/e/yJndg30IBYvEElCHZLd8ebvenP1iSgeY6Ohsrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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