SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '86a80d370a85f4945314b68d26bd39276cd8f68126cb14755f621789f7c92d12' 
  AND token = 'P+jaoZBth9oDOUzLdsy1xsTIRhzckDr8nZMPP9sE6HY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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