SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'aeaf0f20075652d5876311b3c20a38c3c8184c60ee7049c2fc2b44f25ecc7089' 
  AND token = 'RM2X2VblVbVhszKPiezLKpK6wyIjKCp1mdxRMHV7HEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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