SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1ede77fcda30ab7b6541095eada3fc4417d86ac6a8b269d5471cc9145edb39e0' 
  AND token = 'FwtNXBQUHYe1CKyxWGBzg0tfrbV0/dH/2CipdCirCW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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