SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca3f24aed9ecb41f2acb9fac5f4eee11172a4a56bf66cd48cf091d607195c52b' 
  AND token = 'LLk3eoCZsx/rlihxzFsUOjYJBcLvfMdj7zEF6kMSAII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}