SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '828e58e25d7a2377ec2f9619306493f0c07da69a250a1f631f0e5ed213aa264d' 
  AND token = 'FMwcnifglLUAJt2UOfU6S++tTRg0evQ8v9leQtpvH/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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