SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb62a5f1fb1d75829c6323241a39e71daf4e561fbd4db9c3a0f89841760025de' 
  AND token = 'fHZeS25HRawVQq/bQoXy/jAtoCRHKHauS8WI+gE2IJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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