SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7401ac6b5a5bc2f65117222618ab399f471731117178c1fab3eaf2478a845bf6' 
  AND token = 'P/dkwEiPwsx9jaQYSBX0zgcU2iDRIPWHvWsN4AcMY2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}