SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b89787a48bbde6535bf861ddc1729979aba009bad0e44ed8562ba00342b6e300' 
  AND token = 'Tj7u9+wvuLmoEhqx1XvaSLPcDbei9eGnT8u280Pm7vg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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