SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ed7aabe568dfe7d47c4ef572d35aa1d561c4f416d6990a31c4e073794ad4c1a' 
  AND token = 'vdpElarVSQIiMFlPwYVcoeYpWgSfbQEo3lcgP/fKXYM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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