SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9659861570601606bc1a9ba371b64f663e0988fd3e919823bf081af1e90221d' 
  AND token = '7dx5C69F5gm1bHoaS9hcqCqKzOwzvFq7vDoRM58BU/g=' 
  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"
    }
  }
}