SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'de0c14511ddc83539c95019fab92c1a65cd43cb3be5135cd6ee8d02368a7f229' 
  AND token = 'wAIy01hsUymqW1wbnI1I10dHCbQwlw+WQkVbfRMg/ZM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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