SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '691b057153975635960b6aae0b9dd6136df4d5771f450ff680fa60dd6278f9de' 
  AND token = 'd4aOP1WPdfNfNaImpbKBQLkPuBBxC2h0rsNX1+tYBzQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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