SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '822b6256bfa3dd7fb40b4d01023e030012311239710d4c3f8f883a55cc992f65' 
  AND token = 'pEizzsbQFOgvE5+h6/tCkpV6SUhCWTHaKJ870BfTh5U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00122

JSON explain

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