SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f90a771d602d82dc71722cb66eb6318f6617a843e5fffe26f46fb5c32ca4b25' 
  AND token = '9eejogR/cvrAAt8VMqACOgqsmgN2USJATkLlPHP9Few=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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