SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8131f344801061d07a0a2b23cc18b3d3789fdf92378da0fd0b3e555ec981d182' 
  AND token = 'zYBVm5uHf9+kbOzwNoIluw7Ru9ZlvfoymQe05Qt9Dfk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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