SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'fb220cc6d8e7f51cfba673a0770c61a2e5f8c73f1a3435ffc94f14f9a40a3aa7' 
  AND token = 'W0PmFqTy3v10dj/JqVfZUusbzuPTKquh0OwQUsk9E/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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