SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd270d5a27b519d6b7e898f173500047c913074cf3c540d1cd453386527b1140b' 
  AND token = 'BaH0QV+Jdx6UV3qzVfuUXhG7/FG5QzkB3MN8haqLLk4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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