SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1a3d6daa0730b2c04d01d81f777c57ea952c2a8c15f236123f9b5db222e09a0a' 
  AND token = 'vSWoCaYQ/lHvkN0QprHFdwJT8oUN6gTo6OQi9NHp1oY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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