SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ef66aeb23f60dcdb90b4311a09d985ac4a61db15e0448ee2c3cabb7feeeeab8' 
  AND token = 'PdQni2vEK7NrLYZIhXyUkmpySoNWKWGhzZUHMVRsDVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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