SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99c9ebeeb8859ce64f6b34a4a4821ca1943fb528d73ddd3d2c6355710e1b177f' 
  AND token = 'xAYv+leYBJub5PU53+GjSqvwuZ7FrYD3yFvMGcohrnU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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