SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f76cefe4634342299aee3fccf010984f8d65178955db929a26bfdd6417e54699' 
  AND token = 'XFnLN4m+IHEZaAKPYQim615LA1wVvk6hRv1IO5QB+SA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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