SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f11ddc6d6490413c41eb4bd6463d0414ee017ebbf2b2a7279771aba2b56405a' 
  AND token = 'dIjQtuDruRmDWVX6NZ+qPJSLjnwC7EnHJIytbmZYQ54=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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