SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4e483949d5701be3a7a0570db2b1aa591e32231c122d20a48157935418274dc8' 
  AND token = 'iB1JI/k2A76huuSlCfj0FyS/B2WQ6EVHJd8R3vcWjYY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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