SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '070138d6ed5693ed27e85a8764ab5b6dd895064325b537b5b951f5dd67da3c74' 
  AND token = 'rma3/xTfcSmQ0eETrsNu1G1QflWikajugNjD/xQyVHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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