SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b2996849be193fb7bb25f80d46254e450cbd27436956116e4edb59ef30a94fa' 
  AND token = 'uH/Ow7zAdyUHJgetNTmQZdiFeqFgiCCn0h6RCngXfmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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