SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43ff3f00899b682f624d60ab71fcf31548443f4ab02f4c58a4699c72df05dbde' 
  AND token = 'sRj8/G/vMpRPyr2O6bZICUShtQltPHsZ3L5OxtHcLAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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