SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2decfb3fe168982392c7ff7a0aa207bb7fc0c5ea2967fc413e8d54d10873f4f4' 
  AND token = 'ddWfY8qplvjzk4kIll0aLvu9YPyp3nNgctFAeBUkuc0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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