SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f938202fa9f75be28b09e4c362393b32e96a062ca7c332a9a3d1a5689eebf454' 
  AND token = 'E8uL899g/oaVI7w5SJrmJ+iacKHIHdNepmT3FN3dSu4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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