SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32d67c4791a2f6f30819291bd947bf8c426f5b56718647824fe3f0162113bce7' 
  AND token = 'geGppoSR+r4m+4aj3ZWDwXjSDu+QshzmJGE/2Ey70Uk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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