SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '36864b7ed395b467e4a78221930c04b447525cfaa5531d2de2a988f4fbded96c' 
  AND token = 'qU1WyIISywoJQ5jQCzCCa1JELPC0FKoef7/iOHBrfE8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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