SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21e9cc62f7dd214058f0679a2f6539d2df90eddd6585ec4ff4cffc941ab8fbbc' 
  AND token = 'O2tM2tShU9Y7b/6GR2z16umC+lzORBBJAzrZ1Rg0y1c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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