SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ee6c448f6d88ed82d11faf362cbd0a1ad460a73d4c4f56bf335171006f68f3c' 
  AND token = 'mGhJ6zepp/DJu09ZjTH3ViiBnGK+JYvSNX0frgvX5eo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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