SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '467f953de8dda0905325ffe573fbd56fa53674de983cbf2d080144c66525ee3b' 
  AND token = 'MPFaubrZV26p6iJU4MXhs6Crr34OkJLGJP4ECHFNYRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00055

JSON explain

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