SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e05dc6b252cc6aaf4384d7cf789d5c9984e8e22a2cdc2bfc9d8b27043aca88db' 
  AND token = 'a7HruWFO7TPiXbGmrvsfMAE7M3P2RBy6x0h7h/VNM8A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}