SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'edef05663c726fe5c1ff3a00540ee9b0475575202d9893ca4f5492919310a2f6' 
  AND token = 'Us+plCXnq0hK+2/PTnxBHZ48Pw6z4GPkMB+jrel3GaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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