SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9e45f28cf6334a87e4df6cf6f675bb3b7c47373da64452bd69bb3aa24be9213' 
  AND token = 'v++IvwCjGRLeQ/FqXUtInUvZu+8ArnCL4WhrbNCIZ8s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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