SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1699194928724d2c92ac6e1e78691071eba93920114f1712a0b0cfa7eace6072' 
  AND token = 'mw4aoiCDR5R6NnWj1WkwfoCclT54j0eSFpMUA42FRWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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