SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a2f07b5f416ccf1065fb74b44aa50c530a5f900cd8bf2b07d20196f530ec454' 
  AND token = 'Ps91LYHZuDEPUozznsp7F1fCJ0Xw4lMwzCkE8ke6+Hk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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