SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27939c594d852b309a2db8eeecefa564538e02b115a17ccaf58fb32f7f9927cb' 
  AND token = 'nFbwl/sfaQwUvG8gyQSXPUXTK4JKEkqLCCl+TsVFQxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00182

JSON explain

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