SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '377330011aa9ee0ae35c8bb1e4013cecbb994858580a12a444f1b5b98b22dfe5' 
  AND token = 'pK39DNjY9emEfXlpsyQegfDNLoqYPYOZJgQSPabnIfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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