SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4bbaa934f1008dfcca8f86f8a8555bac814352143bf52c7185177479a7bd8eab' 
  AND token = 'E2qLK1SVQk5RJORfkmKWk0FRwzfdO95ijIpWKDxbggs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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