SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2165411a8c76392865f91e4ad4df50c33d3cbe9e3b30117bac18bd8666f6c262' 
  AND token = 'FkZebInqa4k7Ki2iMORDmjyNvpemc2klsEsF+VxTDzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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