SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f21b2f822ad9fe607b3acd42dc10c766fcf92be855ff4e593f4852c8c3cd185d' 
  AND token = '8hxWkl3oZj2mTi/AoekjInytq9GCDYeBoE2uHFpKwAs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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