SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f65c1c906951a82023d98f743d668afbac63babf6007e6ad944024041d4b0224' 
  AND token = 'uZJJguIf0PEf9hFY7X3NmQ5g/wbP+NS76VA14hzRzVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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