SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a22bdbb3b4aeb3dbb4e3f30ac022c5334e78ab3a38909c48ecd412eca6f792f2' 
  AND token = 'Ypq/Z5QxltgPo53FJFdzCfmUhwdFNdfWqCKtb6NLvxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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