SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db6c0860748296eb7d48bafb91f555aca0c52d6f9329934a45f25c47ef041a39' 
  AND token = 'j58YEd8YK05mXu0GgzBWnM8HAsXxPrUpw/LSkekUSYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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